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Abhishek_Singh Bronze Sponsor
Joined: 18 Nov 2010 Posts: 613
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Posted: Mon Feb 27, 2017 9:28 am Post subject: |
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In column detailing section there should be a guideline which says whether we can or cannot provide bars in columns equally on all faces or unequally. SP-16 charts cannot be taken as a clause/directive. Anyways those are obsolete as charts for many higher and commonly used grades are no available.
Analysis for temperature stresses has to be elaborated.
And I want to know very eagerly, where these codes are printed, typed? Does anyone check them or a clerk types and these guys just publish. All the 10000 Indian codes have thousand of typing errors! A national document having so many typing errors reflects the lethargic and lackadaisical attitude of the BIS!
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deepak_gupta SEFI Member
Joined: 12 May 2015 Posts: 7
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Posted: Thu Apr 20, 2017 4:34 pm Post subject: PARAMETERS FOR IS 456 REVISED VERSION |
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Dear Sir ,
There are few parameters which are not mentioned in the code
When we are designing beam , slab , shear walls or any other element for bending , in that case we have to define stiffness modifier parameters for elements in ETAB .
example : we are defining bending coefficient 0.1 for m11 , m22 and m12
for shell element .
or we are defining coefficient for shear wall f11, f22 and f12 say 0.7 .
These values are not there in IS code . In that case we are not sure that which values shall be considered for elements .
If these values can be add in IS code it would be great advantage for analysis of RCC structure in ETAB
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shyamacc SEFI Member
Joined: 27 Dec 2008 Posts: 2
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Posted: Thu May 25, 2017 11:46 am Post subject: |
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Dear All , I feel that IS 456 and IS 10262 should include recommendations or guidelines on SCC mix and SDC mix of 200 to 400mm flow . Type of vibrator for this. 2) Ratio of 20mm aggregates and 12.5mm aggregates for flowable concrete whether to use 40:60 or 30:70 or 20:80 or 10:90 or 100% 12.5 downsize aggregates considering the structural impacts w.rt to earthquake or windloads for high rise buildings . 3) Also concreting procedures for thin walls of 140mm thickness and 3m height for Mivan(aluminium shuttering). 3) Criteria for deshuttering at early ages like 36 hrs or 5 day Mivan cycle. Regards, Shyam Kumar Sahadevan BE (Civil) Manager QA/ QC
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B.V.Harsoda General Sponsor
Joined: 19 Jan 2009 Posts: 2329 Location: RAJKOT,GUJARAT, INDIA
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Posted: Thu May 25, 2017 5:53 pm Post subject: |
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Dear Er. Kumar Sahadevan,
It is looks that as a QC/QA Manager, you are not aware about IS 10262 Revision. For this Refer my previous post at below link:-
http://www.sefindia.org/forum/viewtopic.php?p=76546
The above link is about the IS 10262 for Concrete Mix Design Under Revision and BIS Draft For Comments:-
GUIDELINES FOR CONCRETE MIX PROPORTIONING (Second Revision of IS 10262) ICS No. 91.100.30
Direct Link:
http://www.bis.org.in/sf/ced/CED2(11290)_30012017.pdf
Best Wishes,
Er. B. V. Harsoda
shyamacc wrote: | Dear All , I feel that IS 456 and IS 10262 should include recommendations or guidelines on SCC mix and SDC mix of 200 to 400mm flow . Type of vibrator for this. 2) Ratio of 20mm aggregates and 12.5mm aggregates for flowable concrete whether to use 40:60 or 30:70 or 20:80 or 10:90 or 100% 12.5 downsize aggregates considering the structural impacts w.rt to earthquake or windloads for high rise buildings . 3) Also concreting procedures for thin walls of 140mm thickness and 3m height for Mivan(aluminium shuttering). 3) Criteria for deshuttering at early ages like 36 hrs or 5 day Mivan cycle. Regards, Shyam Kumar Sahadevan BE (Civil) Manager QA/ QC |
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shyamacc SEFI Member
Joined: 27 Dec 2008 Posts: 2
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Posted: Sun May 28, 2017 6:51 am Post subject: Size of Mix design |
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Dear Sir , My concern in mix design for workability in thin walls 140mm for high rise building is that up to what percentage the 20mm aggregates can be reduced for workability without affecting the compressive strength , bond strength with steel and impact strength . Since the Young's modulus of concrete reduce with decrease in size of aggregate and increase in paste content , concrete will crack early . Also as per Table 6 of IS 456 , the cement content to be increased when percentage of 20mm is reduced in mix design drastically if I am right.
Can we use self compacting concrete with only 12.5mm aggregate for shear walls , columns , beam and slab of a G+22 floors residential building ? Will any structural consultant accept such a mix design . Please clarify. Regds, Shyam Sahadevan.
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mhatre.sd SEFI Member
Joined: 07 May 2009 Posts: 1
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Posted: Fri Jun 16, 2017 10:52 am Post subject: Is it true that there is proposal for making minimum width of column as 300mm. |
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Is it true that there is proposal for making minimum width of column as 300mm.
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B.V.Harsoda General Sponsor
Joined: 19 Jan 2009 Posts: 2329 Location: RAJKOT,GUJARAT, INDIA
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Posted: Fri Jun 16, 2017 1:34 pm Post subject: Re: Is it true that there is proposal for making minimum width of column as 300mm. |
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As per cl. 7.1.1 of IS 13920:2016 The minimum dimension of column shall not be less than
(a) 20 times dia. of largest bar in beam at joint.
(b) 300 mm
mhatre.sd wrote: | Is it true that there is proposal for making minimum width of column as 300mm. |
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BVRAO General Sponsor
Joined: 21 Sep 2009 Posts: 50
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Posted: Sun Jun 18, 2017 1:32 pm Post subject: Re: Proposed REVISION OF IS:456-2000- Inviting Comments |
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Column Design for Axially Loaded Biaxial Bending
As per the SP-16 Clause :
3.2.3.3 Charts for compression with bending -
Charts for rectangular sections have been
given for reinforcement on two sides (Charts
27 to 38) and for reinforcement on four
sides (Charts 39 to 50). The Charts for the
latter case have been prepared for a section
with 20 bars equally distributed on all sides,
but they can be used without significant.
error for any other number of bars (greater
than 8) provided the bars are distributed
equally on the four sides.
As per the SP-16 Clause :
3.3 COMPRESSION MEMBERS SUB-
JECT TO BIAXIAL BENDING
Exact design of members subject to axial
load and biaxial bending is extremely
laborious. ( Hence Charts Provided )
But No charts for b'/B ratio of the section . With out these charts Column Design with Two sides Steel is not possible.( Biaxial) .
No Charts for Fe 550 by the IS 456-2000 ( SP-16)
Here under an application to design Rectangular Column for any grade of concrete and steel up to Fe550 , any arrangement of steel pattern ( User defined ) along with interaction diagrams and with exact design calculations with lot of other possible combinations you want.
You can select Minimum spacing , Dia Combinations and economical options.
You can generate Charts for any d'/D , b'/B and any steel arrangement pattern which is not covered in SP-16.
Now my question is how Design Engineers design the Rectangular Column by providing 2 sides steel without b'/B charts ?
Description: |
Chart Which is not covered in SP -16 which is compulsory for Column design with biaxial bending |
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311.96 KB |
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Description: |
Chart Which is not covered in SP -16 |
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190.58 KB |
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616 Time(s) |
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Warning: Make sure you scan the downloaded attachment with updated antivirus tools before opening them. They may contain viruses. Use online scanners here and here to upload downloaded attachment to check for safety.
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Description: |
Software for Biaxial Column Design as per the SP16 up dated on 22/06/2017. This is developed as per the analysis given in SP-16 (IS 456 -2000) Only. |
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Download |
Filename: |
ColumnDesign.rar |
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Last edited by BVRAO on Sat Aug 12, 2017 1:47 am; edited 6 times in total |
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mukeshkumar121in@gmail.co SEFI Regulars
Joined: 02 Jun 2011 Posts: 22
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Posted: Tue Jun 20, 2017 8:00 pm Post subject: Proposed REVISION OF IS:456-2000- Inviting Comments |
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HiOur IS code does not envisage anchor bolt calculation whereas ACI 318 appendix D provides the design of anchor bolt.If this is envisaged in IS-456,it will of good for all practising engineers as well as students.
Regards
Mukesh
On 18 Jun 2017 7:09 p.m., "BVRAO" <forum@sefindia.org (forum@sefindia.org)> wrote: Quote: | Column Design for Axially Loaded Biaxial Bending
As per the SP-16 Clause :
3.2.3.3 Chartsfor compression with bending -
Charts for rectangular sections have been
given for reinforcement on two sides (Charts
27 to 3 and for reinforcement on four
sides (Charts 39 to 50). The Charts for the
latter case have been prepared for a section
with 20 bars equally distributed on all sides,
but they can be used without significant.
error for any other number of bars (greater
than provided the bars are distributed
equally on the four sides.
As per the SP-16 Clause :
3.3 COMPRESSION MEMBERS SUB-
JECT TO BIAXIAL BENDING
Exact design of members subject to axial
load and biaxial bending is extremely
laborious.
The above charts prepared for fck M20 and up to Fe500 for the d’/D ratio 0.05 , 0.10 , 0.15 and 0.20 only
No charts for bars are distributed equally on the TWO sides s with axis of bending perpendicular to the steel .
Practically every column having axial load with biaxial bending . But as per my knowledge there is no analytical solution for Biaxial column design.
Hence SP- 16 Provides Charts. Using these Charts we can design only Four sides equally distributed steel . For Two sides equally distributed steel No charts for axis of bending perpendicular to the steel bars. Hence we can not do design for Two sides equally distributed steel which is economical in most of the cases. More over the calculations are laborious and involve trail and error method and graphical interpolation. Computerisation is not easy.
Here under an application to over come all the above lapses . we can design for any grade of concrete and steel up to Fe550 ,any arrangement of steel pattern ( User defined ) along with interaction diagrams and with exact design calculations with lot of other combinations you want. You can select Minimum spacing , Dia Combinations and economical options . STRESS-STRAIN CURVES FOR COLD-WORKED STEELE ( FIG. 3 ) also developed for Fe 550 steel as asked by the one of the sefian in this postl .
Download Attachments:
Only Fig
Only Fig
Only Fig
Software for Biaxial Column Design as per the SP16
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Nagesh1374 Progressive Member
Joined: 30 Dec 2015 Posts: 48
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Posted: Fri Jun 23, 2017 5:41 am Post subject: Re: Proposed REVISION OF IS:456-2000- Inviting Comments |
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I feel happy as we are going to revise IS 456 Code.
I feel 'Structural Analysis' is very important.
A Chapter on Structural Analysis as in ACI 318-14 may be useful for who are fresher to designing.
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